speed up rust installs, try with cosmic-session-git

[soloturn]

installing rust packages is painful, restarting a package starts from zero. cosmic-session-git is a good example. the 15 components of cosmic desktop use the same libraries, they get built again and again. pressing ctr-c and restarting also starts the build from zero.

it would be cool if there is an easy way to reuse stuff already downloaded and/or built.

[durandj]

Isn't that the --needed flag?

-needed do not reinstall up to date packages